Regulator for variable-speed generators.



' J. B. DYER. REGULATOR FOR VARIABLE SPEED GENERATORS.

APPLICATION FILED NOV. 7'. HH 7. I

Patented Dec; 30,1919.

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WITNESSES: INVENTOR WM 175/70 509w UNITED. STATES PATENTOFFICE.

JOHN B..IDYER, OF PITTSBURGH, PENNSYLVANIA, ASSIG-NOR TO WESTINGHOUSEELECTRIC AND MANUFACTUBING- COMPANY, A CORPORATION OF IfENNSYL- VAN IA.

REGULATOR FOB VARIABLE-SPEED GENERATORS.

To all whom it may concern."

Be it known that-I, JOHN B. DYER, a citizen of the United States, and aresident of Pittsburgh, in the county of Allegheny 6 and State ofPennsylvania, have invented a new and useful Improvement in Regulatorsfor Variable-Speed Generators, of which the following is aspecification.

My invention relates to an automatic regulator for the field excitationof a variable speedgenerator such, for instance, as a generator that 1smounted upon an automob le or other vehicle and is adapted to supplycurrent to a storage battery and to other deing within the structure ofthe generator in connection with which it is used.

My invention is illustrated in the accom} zslpanying'drawing, Figure 1of which is a view in side elevation of a regulator em-- bodying thesame; Fig. 2 is-a plan view of the regulator; and Fig. 3 is a simplediagram illustrating its circuit connections.

The regulator comprises an electromagnet having a U-shaped magnetizablemember 1 that provides the outer legs of the electromagnet, and acentral cylindrical leg or member 2 that is threaded in the member 1 andis provided in its threaded end with a slot for the reception of ascrew-driver for effecting adjustment of the operation of the regulator.The threaded end of the central leg 2 is also provided with a lock nut 3for securing the member in its adjusted position.

The other end of the central leg 3 is somewhat enlarged so as toconstitute the main pole'of the electromagnet. The central leg 2 issurrounded by a main energizingcoil 4 that is connected in 'shuntto thearmature of the generator 28 in connection with which the regulator isused. In some cases, it may be preferable or desirableto employ a smallserles coil-6 also which is adapted to be connected in series with thearmature 5, as

shown in Fig. 3, and preferably arranged to oppose the coil 4.

Attached to the ends of the U -shaped 4 and 6 areconnectedi The coremember Specification of Letters Patent. I Patented Dec. 30, 1919.,

' v y (p Application filed November 7, 1917. Serial Nfo. 200,663. I

plate 9. The armature 11 is restrained from I engagement withthe end ofthe member 2 by means of two plate springs 13 and 14 that are ivotedthereto at one end, the free end of the Spring 13 engaging a stop or lug15 that constitutes a part of the plate 9. The

. spring 13 is bi-metallic, that is, it is composed of two differentmetals, such as nickel and steel, that have difierenttemperatureeXpansion-co-eflicients, for a reason which will be more fully explainedhereinafter.

The free end of the spring 13 is separated somewhat from the spring 14in order that it may serve as the main restraining means forthemovements of the armatureunder normal conditions.

Attached to the, spring l4 is a contact' member 17 that 1s adapted toengage and disengage a cooperating contact member 18 carried by anotherplate spring 19, one ,end'

of which is rigidly attached to the 'U-shaped magnetizable core by meansof the. rivets 8,

insulating pieces 21, however, being em -ployed to insulate the bracketfrom'the other parts of the regulator. The bracket 20 is .also providedwith an ear or lug 22 to per mit of connecting the same to the circuitto be controlled by the regulator. Attached to the free end of thespring 19 on the side opposite the contact member 18 is a fiber, or

other suitable wear piece, 23'that is adapted to engage a cam oreccentric 24 mounted upon or driven by the shaft of thegeneratortheie'xcitation of which iscontrolled by the regulator. Whenthe generator speed and voltageattain predetermined values the armature11 is attracted and the, contact member 17 is raised slightly. The cam01' eccentric 24 then serves to vibrate the contact member 18- into andout of engagement with the member 17 at a rate proportionate to anddependent upon the speed of the generator. The plate 9 is provided witha lug or car 25 to which theends of the coils the device being connectedto ground, the

terminals of the coils and the contact member 17 are thus grounded.

The contact member 18 is connected to a suitable point in a resistor 26a portion of which is .included in series with the shunt field magnetwinding 27 of the generator and disengagement of the contact members 17and 18. The position of the contact member 17 depends upon the degree ofexcitation of the electromagnet produced by the coils 4 and 6 which areconnected in opposition to each other. Thus, as the voltage of thegenerator increases, the contact member 17 is caused to recede from theterminal 18 so that the eflective value of the resistance in the fieldcircuit will be somewhat increased .to efiect a reduction in theexcitation of the field magnet winding and,'therefore, of the voltage ofthe generator. Likewise, as the current delivered by the generatorincreases, the current in the coil- 6 increases correspondingly. Sincethe magnetizing eifect of this coil is opposed to that of the coil 4,the pull upon the armature is somewhat decreased so as to permit of areduction in the effective value of the resistance of the resistor 26,and, therefore, of an increase in the excitation of the field magnetwinding which increases the voltage to enable the generator to carry theincreased load without'substantial reduction in its voltage.

"As the generator temperature increases, due to its operation underload, the'increased temperature is communicated to the bimetallic platespring 13 and, owing to the different rates of expansion of the twometalsv which compose it, the restraining force of the springupon the,armature is somewhat decreased in accordance with the increase in thetemperature of the generator structure. The efiect of the decreasedrestraining force of the spring is to make it possible for a smallercurrent in the series coil 6 to cause an increase in the efiective valueof the resistance in the field circuit sothat the generator will tend tocarry less. load after it has become heated than when cool. Theresistances of the regulator. coils 5 and 6 will also change withchanges in temperature, and the bi-metallic spring 13 also operates tocompensate for such changes. Similarly, the operation of the regulatorwill be effected by atmospheric temperature so that, when the weather iswarm the regulator will cause the generator to deliver less current at agiven speed than when the weather is cold.

The structure of the electromagnet may also be employed in other devicesthan regulators, such, for instance, as cut-out devices employed forcontrolling the connections of a generator to a battery that is adaptedto be charged thereby when the voltage of the generator exceeds thevoltage of. the battery.

. I claim as my invention:

1. A regulator for dynamo-electric machines comprising an electromagnethaving an energizing winding, an armature therefor that ispivoted at oneend, a plate spring attached to the armature and extending beyond itsfree end, a stop with which the said spring engages, a pair ofcooperating contact members one of which is actuated by the armature,another plate spring on one end of which the other contact member ismounted and the other end of which is rigidly supported, and means foractuating the latter spring,

2. A regulator for dynamo-electric machines comprising an electromagnethaving an energizing winding, an armature therefor that is pivoted atone.end,- a lei-metallic plate spring attached to the armature and 9extending beyond its free end, a stop with which the said springengages, a pair of cooperating contact members one of which is actuatedby the armature, another plate spring on one end of which the other con-9 tact member is mounted and the other end of which is rigidlysupported, and means for actuating the latter spring. v 3. A regulatorfor dynamo-electric machines comprising an electromagnet having 1 anarmature pivoted at one end, a plate spring attached to the armature andextending beyond its free end, a stop with which the said springengages, a pair of cooperating contact members one of which is'actuatedby the armature, another plate spring on one end of which the othercontact member is'mounted and the other end of which is rigidlysupported, a wear piece attached to the latter spring, and a cam thatengages the said wear piece and is actuated by the dynamo-electricmachine.

.4. A regulator for a dynamo-electric machine comprising a U-sh-apedmagnetizable member, a central adjustable leg therefor, I

an energizing winding surrounding the saidcentral leg, an armaturepivoted to one of the outer legs of the magnetizable member andextending adjacent to the central leg,

a plate spring attached to thearmature and 1 extending beyond its freeend, a stop with which the said spring engages, .a pair'of cooperatingcontact members one ofwhich is actuated .by the armature, another ,platespring upon one end of which the other conj tact member is mounted andthe other end of which is rigidly supported, and a cam driven by thedynamo-electric machine for actuating the latter spring. 1

'5. A regulator for a dynamo-electric inaj chine comprising a U-shapedmagnetizable member, an adjustable central leg therefor, an energizingwinding surrounding the central leg, an armature that is pivoted to oneof the outer legs of the magnetizable memher and extends adjacent to thecentral leg, two superposed plate springs one of which isbi-metallic,'at tached to the armature and extending beyond its freeend, a stop with which the said springs engage, a pair of cooperatingcontact members one of which is actuated by the armature, another platespring upon one end of which the other contact member is mounted and theother end of which is rigidly supported, and a cam driven by thedynamo-electric machine for actuating the latter spring.

6. A regulator for a dynamo-electric machine comprising a U-shapedmagnetizable member, an adjustable central leg therefor, an energizingwinding surrounding the central leg, a non-magnetizable plate attachedto the ends of the legs of the magnetizable member, an armature that ispivoted to said plate and extends across the end of the said centralleg, a bi-metallic plate spring attached to the armature and extendingbeyond its free end and engaging a portion of the said non-magnetizableplate, a pair of cooperatingcontact members one of which is actuated bythe armature, another plate spring upon one end of which the othercontact member is mounted and the other end of which is rigidly attachedto but insulated from the non-magnetizable plate, and a cam driven bythe dynamo-electric machine for actuating the latter spring.

7 An electromagnetic device comprising a U-shaped magnetizable member, acentral adjustable core leg mounted in the said member, an energizingwinding surrounding the said central leg, an armature pivoted to on ofthe outer legs of the magnetizable member and extending adjacent to thecentral leg, aplate spring attached to the armature and extending beyondits free end, a stop with which the said spring engages and a pair ofcooperating contact members one of which is actuated by the armature.

8. An electromagnetic device comprising a U-shaped magnetizable member,a central longitudinal adjustable core leg mounted in the said member,an energizing winding surrounding the said central leg, anon-magnetizable plate attached to the ends of the legs of themagnetizable member, an armature that is pivoted to the said plate andextends adjacent the end of the said central leg, a plate springattached to the armature and extending beyond its free end and engaginga portion of the said magnetizable plate, and a pair of cooperatingcontact members one of which is actuated by the armature.

In testimony whereof, I have hereunto subscribed my name this 30th dayof Oct.,

JOHN B. DYER.

